https://doi.org/10.1140/epjst/e2008-00779-6
Measurement of transversity signals in two hadron production at COMPASS
1
Helmholtz-Institut fuer Strahlen- und Kernphysik,
Universitaet Bonn, Nussallee 14-16, 53115 Bonn, Germany
Corresponding author: massmann@iskp.uni-bonn.de
The quark structure of the nucleon at the twist two level
can be completely described with three quark distribution functions:
the spin averaged distribution function q(x), the helicity
distribution 
and the transverse spin distribution
. This last function, referred to as
transversity, is chiral-odd and can only be measured in combination
with another chiral-odd function. COMPASS is a fixed target
experiment at the CERN SPS M2 beamline. Its target
(
) can be both longitudinally and transversely
polarized with respect to the polarized 160 GeV/c 
-beam. In
transverse configuration can be
measured in semi-inclusive deep-inelastic scattering (SIDIS),
requiring the detection of hadronic products. A rather new probe of
the transverse spin distribution function is
the measurement of two hadron production, introducing the chiral odd
interference fragmentation function
. Results are presented for
the years 2003–2004 including particle identification by using the
information of the RICH detector. The analysis was performed using
all positive/negative charged pairs and z-ordered pairs.
© EDP Sciences, Springer-Verlag, 2008
